Refrigeration



Feb. I, 1944.

c. c. zooms 2,340,414 REFRIGERATION Filed July 8, 1939 5' Sheets-Sheet 1 INVENTOR Curlz's 6. (0008 a lazpdw ATTORNEY Feb. I, 1944. c. c. COONS 2,340,414

REFRIGERATION I Filgdfluly 8, 1939 5 Shets-Sheet 2 INVENTOR ATTORNEY Feb. 1, 1944.

c. c. COONS 2,340,414

REFRIGERATION '5' Jo/eno/c/ I a/ve C/rcu/afar Mofor INVENTOR Cyril's C. Coons May 5.

ATTORNEY *taneously admits fuel to the burner.

means fuel is not admitted to the burner unless Patented Feb. 1, 1944 I 2,349,414 REFRIGERATION Curtis 0. Goons, North Canton, Ohio, assignor to The Hoover Company, North Canton, Ohio, a

corporation of Ohio Application July 8, 1939, Serial No. 283,357

19 Claims.

This invention relates to the art of absorption refrigerating systems and more particularly to a novel control mechanism particularly designed for use therewith.

In prior absorption referig erating apparatus it is customary to provide a constantly burning pilot for igniting the combustible fuel burner which heats the refrigerant vapor generator. In addition, some means must be provided for igniting the pilot initially and also for igniting the same in the event that it is accidentally extinguished. This possesses a number of disadvantages among which may be mentioned the necessity for auxiliary igniting apparatus and the necessity for a constantly operating burner which consumes an appreciable amount of fuel which does not measurably contribute to the operation of the system. The apparatus must be so designed and arranged that the generator and its associated burner can be positioned in the cabinet in a manner to permit the operator to obtain ready access to the burner and its associated pilot in order to ignite the same when necessary. The combined effect of these factors results in' a decrease in the efliciency of the system, an increase in the operating cost thereof, a design of apparatus not ideally suited for arrangement within the cabinet, an appreciable waste of fuel and the incorporation in the system of auxiliary equipment which has no operative function with respect to the production of refrigeration and which is rarely used even though necessary.

Accordingly, it is a principal object of the present invention to provide a three-fluid absorption refrigerating system and associated control and i It is a further object of the present invention to provide an absorption refrigerating apparatus of the type utilizing a pressure equalizing medium circulator which apparatus includes a control and burner assembly so constructed and arranged that energization of the circulator, the supply of fuel to the burnerand ignition of the gas are all simultaneously controlled in a simple eflicient manner. 7 7

It is a still further object of the present invention to provide an apparatus of the character above referred to in which the fuel burner is opened to admit fuel to the burner simultaneously with energization of the inert gas circulator and in which a safety valve is maintained in open position after initial opening-movement'thereof by heat radiated from the generator heating unit after de-energization of the electrical starting apparatus, I

It is another object-of the invention to provide a fuel burner and ignition arrangement in which fuel is supplied to the burnerfonly after energize.-

- tionzof the igniting apparatuii.

It is still another object of the present invention to provide a burner of the character above described in which the igniting apparatus is automatically de-energized and moved out of the path of flame issuing from the burner very shortly after ignition of the burner.

Other objects and advantages of the invention will become apparent as the description proceeds when taken in connection with the accompany ing drawings in which! burner mechanism which will eliminate the necessity for a constantly burning pilot which will desired part of the cabinet construction without regard to its availability to the operator for ignit- I ing or'other purposes, all of which contribute greatly to the production of an economical, chi-- cient commercially acceptable unit. I It is a principal object of the invention to pro-- vide-a refrigerating apparatus including a fuel burner for heating the boiler which is provided with an. electrical igniting device connected in circuit with the circulating motor in such fashion that energization of the electric circuit by the control causes operation of the igniter and simul- By this igniting conditions are met.

"tion refrigerating invention. I I

Figure 2 is a fragmentary rear elevational view Referring now to the drawings in Figure 1 is a partly diagrammatic and partly elevational sectional view of a three-fluid absorpsystem embodying the present of the apparatus shown in Figure 1.

Figure 3 is a partial sectional view on an enlarged scale .of a burner and igniting apparatus.

Figure 4 is a schematic wiring diagram 'of the control mechanism. I Figure 5' is-an elevational view partly in section of a modified form ofthe invention. I

Figure 6 illustrates a detail of the apparatus disclosed in Figure 5 I V Figure 7 is a view taken on the line 1-1 of Figure-6.

I I detail and first to Figures 1 and 2 thereof, there is disclosed a three-fluid absorption refrigerating system comprising a boiler an analyzer D, an air,- cooled rectifier R,.a' tubular air-cooled condenser II C, an evaporator E. a as heat exchanger Ci, an

.erating system including a plurality of gas and liquid circuits to which reference will be made in more detail hereinafter.

The above described refrigerating system will be charged with a suitable absorbent, such as water, a suitable refrigerant, such as ammonia, and an inert pressure equalizing medium, preferably a dense inert gas like nitrogen.

The application of heat to the boiler B generates refrigerant vapor therefrom which passes upwardly through the analyzer D in contact with strong solution flowing downwardly therethrough. The refrigerant vapor is conveyed from the analyzer D to the upper portion of the condenser C by means of a conduit I l whichineludes the air-cooled rectifier R. The refrigerant vapor is liquefied in the condenser C and is conveyed therefrom to the bottom portion of the evaporator E by means of the conduit I2 which includes a downwardly extending U-sli'aped loop portion 13 to form a pressure balancing liquid column. The condenser side of the loop I3 is vented to the rich gas side of the gas heat exchanger G by means of a conduit I4. I

The lean solution which is formed in the boiler by the generation of refrigerant vapor is conveyed therefrom to the solution reservoir S by way of the conduit Hi, the liquid heat exchanger L, and a conduit l l which includes a loop portion provided with air-cooling fins to form a solution pre-cooler. The lean solution is elevated from the reservoir S into the upper portion of the absorber A by means of a gas lift pump conduit l9.

Pumping gas is supplied to the lower portion.

cooling air flowing over the fins mounted on theexterior walls of the absorber conduit.

The strong solution formed. in the absorber is conveyed from the bottom portion thereof to the upper portion of the analyzer D by means of the conduit 25, the liquid heat exchanger L, and the conduit 25, thus completing the absorption solution circuit.

The lean inert gas formed in the absorber is conveyed from the upper portion thereof into the suction inlet of the fan F by the conduit 23. The

, lean gas is then placed under pressure by the fan F andis conveyed therefrom to the bottom portlon of the evaporator E by means of the conduit 2|, the gas heat exchanger G, and the evaporator inletconduit 21.

The evaporator E is shown diagrammatically herein and it may take any desired form of construction. However, a. preferred construction is disclosed and claimedin the co-pending appli- The evaporator is constructed of relatively small diameter tubing whereby the inert gas travels therethrough with a velocity suflicient to sweep or drag the liquid refrigerant through all portions thereof as it is evaporating. The evaporator is also provided with an enlarged diameter finned box-cooling conduit 28, which is tilted slightly rearwardly in order that the liquid refrigerant may flow therethrough by gravity as the velocity of the gas stream in the boxcooling conduit is insuficient to propel the refrigerant. The rich gas formed in the evaporator is conveyed from the box-cooling conduit 28 to the bottom portion of the absorber A by means of the conduit 29, the gas heat exchanger G, and the conduit 30. A suitable overflow drain 3| is connected between the bottom portion of the evaporator E and the strong solution return conduit 25.

As may be seen clearly in Figure l, the above described apparatus is associated with a cabinet which comprises an insulated refrigeration chamber 33 overlying a mechanism chamber 3fl. The cabinet also includes a rear vertical aircooling flue 35. Cooling air may be admitted to the compartments 34 and 35 in any desired manner as by louvres in the rear walls. of the compartment 35 and in the bottom wall of the compartment 34.

The refrigerating apparatus will be mounted upon a suitable frame (not shown) which will be associated with the cabinet construction and will be secured thereto.

The arrangement of the apparatus with respect to the cabinet will now be described. The boiler B. is positioned in the chamber 34 directly beneath the flue 35 at the rear lower corner of the cabinet assembly.

The tubular inclined absorber A extends forwardly and downwardly from a position directly beneath the bottom portion of the flue 35 and into the compartment 34. The rectifier and condenser are positioned at the intermediate and upper portions of the flue 35, respectively. 7 The evaporator is positioned within the compartment 33 and the gas heat exchanger is embedded in the insulation of the rear wall thereof.

As is illustrated in Figures 1 and 2 the boiler analyzer liquid heat exchanger assembly is encation of Curtis C. Coons and William H. Kitto,

Serial No. 386,196, filed April 2, 1941, now Pat out No. 2,328,196, dated August 31, 1943.

A control mechanism for the apparatus is indicated generally at 40 which will be responsive to thermal conditions at the evaporator or within the space 33 as may be desired. The control mechanism All is supported on a suitable framework indicated generally at M and is provided 'with a regulating dial 42 positioned in a recess 43 formed in a closure panel 44 for the compartme'nt 34. The mechanism 40 may be of any desired type, a preferred construction being disclosed in my co-pending application, Serial No.

148,424, filed June 16, 1937, now Patent No.

2,228,343, dated January 14, 1941.

The mechanism 40 will include a simple switch for controlling the energization of the motor M which drives the circulating fan F and it also operates a gas valve 45 which is carried by the facing the gas inlet conduit 41.

. disc element 6|.

mechanism 46. Gas is supplied to a burner 46 which is positioned to heat the boiler B, as will be disclosed in more detail hereinafter, by means of a conduit 41 passing through the valve 45.

Referring now more particularly to Figures 3 and 4 the construction of the gas burner and igniter assembly will be described.

The gas burner, igniter and valve assembly 46 v is' supported from the insulating block 31 by a suitable bracket 48 which is attached to the main burner casting 56. The casting 56 is provided with an internal bore which receives a valve seat plug which is provided with a valve seat 52 The valve seat 52 corrmiunicates with an annular passage 53 formed therearound by means of a central bore 54 and radial passageway 55. The annular passageway 53 communicates with the laterally extending duct 56 formed in a portion of the casting 56. The valve seat plug 5| is threadedly received by the main casting so and a suitable gasket 66 is provided at the joints therebetween to prevent gas leakage.

The valve seat 52 is designed to cooperate with a valve element 5! which is carried by an actu ating shaft 58 passing through the valve seat element 5|.

The lower end of the shaft 58 is suitably secured and sealed to a snap-acting thermostatic The outer edges of the disc 6| are crimped and sealed into a supporting cup 62 which is carried by the valve seat plug 5I and is secured thereto by means of a nut and sealing gasket indicated at 63. A suitable arcuate shielding disc 64 is also secured in the supporting cup sleeve 11 in order to maintain the same in proper relationship with the burner tube. A small spring washer 82 is positioned between the conduit I6 and the adjacent ends of the sleeves I1 and I8 in order to maintain a frictional engagement between the ends of the sleeve I1 and the small tongue 8I. The size of the primary air opening I6 is thereby adjustable simply by turning the outer sleeve- I6 which is rigidly attached to the control sleeve II.

In order to provide heat to actuate the snap acting disc initially in a manner to move the valve 51 to open position, an electrical heating unit of the so-called Calrod type is wrapped around the supporting cup 62 for the disc 6|; The

heating unit is shielded by means of a refractory cup 85 which is constructed of porcelain or similar material. The cup 85 is held in position. between the base portion of the cup 62 and a gasket 86 which rests. upon a shoulder formed on the valve plug body 5|.

In order to maintain the disc in open position after the heating unit 84 has been de-energized a heat conducting finger 88 is clamped to the outer edge of the cup 62 and extends downwardly adjacent the end of the tube I2 in position to be heated by flame issuing from the tube I2. In

this way heat is conducted from the flame through the finger 88, the disc 6I to maintain the same in upwardly flexed/position; that is, in the position opposite that illustrated in Figure 3 whereby to maintain the valve plug 51 away from the seat 52 to permit gas to flow to the burner 'tube 12.

62 and is provided with a central opening through which passes an actuating cap 65 of insulating material which is carried on the lower end of the shaft 58.

The end of the passageway 56 remote from thevalve plug 51 is threaded and receives a metering orifice plug 68 which is adjusted by means of a needle .valve 69 also threadedly mounted in the extension 56. A downwardly extending duct I6 extends from the conduit 56 beyond the metering plug 68. a

A burner tube I2 is threadedly mounted on a nipple I3 on the lower end of the conduit 16. ,The nipple I3 and the lower end of the conduit I6 are provided witha central bore I4 which communicates with the burner tube I2. A gas jet plug I5 is threadedly received in the burner end of the bore 14 to'project the gas into the central portion of the tube I2.

The tube I2 is provided with a suitable primary air inlet I6 adjacent the nozzle plug I5. A primary air control sleeve 11 is rotatably mounted on the exterior wall .of the burner tube I2 adjacent the nozzle plug I5 in order to'regulate the,

In order to ignite the burner I2 a loop ignition wire 96 is mounted adjacent the end of the tube I2. The coils 96 rest upon a refractory support 9| which is constructed of porcelain or similar material and the ends of the element 96 are secured by electrical conducting bolts 92 which pass through the refractory 9|. The refractory 91 is supported by an arm 94 carried by the mairl' casting 56. Electrical contact between the arm 94 and the conducting bolts 92 is prevented by means of shoulders 95 on the refractory 9| which pass through openings in the support 94. A sheet of mica or similar material 96 is interposed between the securing and contacting nuts on the bolts 92 and the support 94.

The energization of the heating element 84 and of the ignition element 96 is under the control of a switch mechanism indicated generally at 91. The switch mechanism is suitably supported on an extension 98 of the conduits 56 and I6 and includes a pair of switch arms 99 and I66 normally supported in spaced relation. The switch arms 99 and I66 are supported from the element 98 and are insulated therefrom by well known construction. The upper and longer arm 99 extends into the path of movement of the cap of the burner tube I2 and in concentric relationv I of the sleeve I8 to maintain the proper space relations between the burner tube and the air sleeve. I I

The burner tube 12 is provided with a struckup portion M which abuts an end portion of the I arrangement is such that movement of the valve plug 51 into sealing relation with the valve seat 52 to discontinue the supply of fuel to the burner I tube I2 causes the cap B5 to urge the switch arm 99 downwardly, as viewed in Figure 3, into contact with the switch arm I66;

the end'of the burner tube 12.

91 connects directly to one side of the igniting loop 90 and to the heating element 84 by means of a conductor I01. The other sides of the loop 90 and of the heating coil 94 are connected to the control .mechanism 40, which includes .an electrical switch, by means of conductors I09 and I09, respectively. The motor is also connected to the conductor I09 by means of a conductor 0. The control 40 is connected directly to the line wire I05. 7

The operation of .this form of the invention is as follows: Assuming that there is a demand for refrigeration the thermostatic mechanism within the box 40 will actuate the gas valve 45 to open position whereby gas will be supplied to the safety control valve 51. The mechanism 40 will also close the circuit between the conductors I and I09. This will immediately energize the circulating motor M whereby the inert gas will be circulated by the fan F.

As the valve 51 will be in engagement with the seat 52 the switch contacts 99 and I00 will be in engagement whereby the heating coil 94 and the igniting loop 90 will also.be energized. A few seconds after energization of the heating coil 94 the heat'generated thereby will stress the thermostatic disc 6| sufficiently to cause the same to snap upwardly, as viewed in Figure 3, to disengage the valve plug 51 from the seat 52 whereby fuel will be supplied to the burner 12. Slightly before the disc 6| has actuated the valve to open position, the igniting loop 90 will have become incandescent and will ignite the gas issuing from Immediately the valve 51, 58 is snapped to the open position the contacts 99 and I00 move to open position and de-energize the heating coil 84 and the igniting loop 90. However, there is sufflcient heat in the valve assembly to maintain the disc 6| in valve opening position until the heat conducted from the flame through the finger 89 is sufficient to maintain it in that position as long as the flame is present on the burner 12. Likewise the residual heat in the incandescent igniting loop 90 is sufilcient to maintain the same in incandescent igniting condition for the small fraction of a second required for the gas to pass from the valve seat 52 to the flame shield 19 of the burner tube 12.

This construction entirely dispenses with the cost of the constantly burning pilot and the need for manual ignition for the boiler heating burner and its pilot. By this construction the burner is supplied with fuel only after energization of the igniting loop wherefore ignition is positively assured.- It is also worthy of note that the igniting circuits are broken immediately the safety valve moves to open position whereby any failure of flame at the burner" will cause rapid closure of the safety valve by the thermostatic disc 6| to prevent the escape of. raw gas from the burner tube. This provides a repeating igniter in the event of failure of ignition at the burner. Should the fuel fail to ignite for any reason after energization of the starting coil 84, the valve will remain in open position for a very short period of time only before the thermostatic disc returns .it to closed position. The quantity of unburned fuel which could escape in this period of time is too small to create a, dangerous'condition. As-

suming failure of ignition the igniter and startcycle would be initiated, 1

Referring to Figures 5 to '1. there is disclosed a modified form of the invention. Certain portions of this apparatus are identical with portions described in connection with Figures 1 and 2 and are giventhe same reference characters primed, Except as is indicated in Figures 5, 6 and '1 this form of the invention is identical with that previously described and is designed and intended to be utilized with the same type of refrigerating system and in the same general environment. Therefore, only the burner, igniter and control system have been illustrated as they are the only portions which differ in any way from those described in Figures 1 to 4.

I In this form of the invention the control mechanism I operates an electrical switch only. Gas is supplied to the burner 10' by means of the conduit I5I in which there is interposed a solenoid control valve I52.

The burner construction does not include a safety cut-off valve as that function is performed by the solenoid valve and its controls. The conduit I5I merely connects directly into a supporting housing I which includes a suitable conduit connected tothe nozzle of the burner assembly. The burner and associated housing I55 are supported from the boiler insulation by means of a bracket I56 which positions the burner to discharge the products of combustion into the boiler flue 38 A block of insulating material I51 is suitably supported upon the bracket I56 and. at its upper end carries a, laterally spaced pair of U-shaped electrical conductors and switch contacts I58 and I59 which are made of spring material.

The U-shaped spring switch contacts I58 and I59 are attached to the block of insulating material I51 by means of attaching and connecting bolts I6I which pass through the arms of the switch contacts I58 and I59 adjacent the bight portions thereof and through spacing blocks of insulating material I60. v

A thermostatic bar I is suitably supported upon the insulating block I51 between the switch arms I58 and I59. A sheet of mica or similar material I66 is attached to the extending end of the thermostatic element I65. A loop igniting wire I61 has its ends attached to laterally extending wings I68 of the mica I66. The wings I68 extend between the ends of the resilient U- shaped switch elements I58 and I59 and carry contacting rivet elements I69 to which the ends of the wire I61 are attached and which are positioned to contact the upper arms of the U-shaped resilient switches I58 and I59 on opposite sides of the thermostatic bar I65.

An electrical conducting bar I10 is' rigidly secured to the thermostatic bar I65 by means of a pair of rivets I1I which also serve to secure the mica. The conducting bar I10 is insulated from the thermostatic strip by means of a strip of insulating material I12. The outer ends of the ,bar I10 are provided with protuberances I13 As can be seen in Figure 5, the outer ends of the thermostatic bars I65 and the igniting loop which is carried thereby are positioned slightlybeyond the end of the burner and when cool the thermostatic bar flexes upwardly in the position shown/in Figure 5 to bring the loop I61-into the path of flow of fuel issuing from the end of the burner whereby to ignite the same. In this position the .upper arms of the switching elements I58 and I59 are in contact with the buttons I69 elements result of the downward flexing of the thermo--' and are flexed upwardly as is illustrated in Fi ures and 6. In this position also the protuberances I13 are raised from and are out of contact with the lower arm of the l J-shaped switching element.

Electrical energy is supplied to the apparatus from a pair of supply conductors I15 and, I16. The conductor I15 connects directly to the switch arm I59 and to the motor M by means of a con ductor I11. The conductor I16 connects to the thermostatic mechanism I50 which in turn is connected to the solenoid valve and to the circulating motor by means of conductors I18 and I19, respectively. The solenoid valve is connected to the switch arm I58 by means of an electrical conductor Ian.

The operation of this form of the invention is as follows: Assumethat the temperature conditions of the refrigerator are such that the control mechanism I50 has broken the circuit between the lines I16 and I18. The thermostatioelement I65 will be relatively cool and will be flexed upwardly into the position illustrated in Figures 5 and 6. When the temperature of the refrigerator rises in response to demand for refrigeration, the thermostatic mechanism I50 will close the circuit between the conductors I16 and I18. The circulating motor will immediately be energized through the following circuit I16, I50, I19, I11 and I15. The solenoid valve will be moved to open position andthe igniting loop I61 will be energized as follows: I16, I50 and I18, I88, I58, I69, I61, I69, I59 and I15. Energization' of the solenoid valve will cause fuel to be supplied to the burner which will be ignited by the incandescent loop I61 immediately it issues therefrom. Shortly after ignition of the fuel supplied to th burner the combined heat of the incandescent wire and of the burner will heat the thermostatic element I65 and will cause the same to flex downwardly, as viewed in Figures 5 and 6, which will break the engagement between the upper arms of the switch elements I58 and I59 and the contact buttons attached to the ignition wire I 61. However, the circuit will be maintained closed by engagement between the con-' ductor I and the lower arms of the switching I58 and I59; Therefore, the net static element I65 is to remove the igniting loop from the path of the flame issuing from the I burner in order to protect the same from dele-.

will immediately cause the thermostatic element upon which the igniting loop is mounted to flex to a position to energize the igniting loop. In

, the event of current failure which would prevent energization of the igniting loop, no gas could be supplied to the burner as it will be impossible to energize the solenoid valve I52. In short, this form of the invention provides an I arrangement in which it is imposisble to supply fuel to the burner unless the igniting device is conditioned for energization.

The present invention provides an absorption refrigerating system in which the boiler and its associated burner assembly may be positioned in,

any part of the cabinet without regard to the accessibility of the burner for ignition by the operation. In addition, it is impossible for raw gas to escape from the burner under any condition of operation and no loss is sustained by maintaining a continuously operating pilot burner and its associated manual ignition mechanism.

The absorption refrigerating apparatus and its associated control disclosed herein provides a unique integration of the various pieces of apparatus in such fashion that the normally controlling gas valve, the safety cut-off valve of the burner and the ignition mechanism thereof are all under thedirect control of the refrigeration demand regulating mechanism.

A feature of peculiar advantage resident in the instant invention results from the fact that the normal control mechanism for the refrigerating apparatus has direct control of the energization and ignition of the fuel burner after which the I ignition mechanism is de-energized without permitting the escape of raw gas from the burner and without interferring with the control exercised by the refrigeration demand responsive mechanism over the fuel burner.

A most compact and fficient form of construction of the apparatus is rendered possible by the arrangement herein disclosed because the, boiler and its immediately associated mechanism may now, be placed in a portion of the apparatus remote from the front of the cabinet and directly beneath the cooling flue whereby compactness of the assembly is promoted and the lengths of the various conduits interconnecting the various elements is reduced to a minimum. This is ma- I terially advantageous both from the constructional and functional viewpoints for obvious reasons.

While variousforms of the invention have been illustrated and described in considerable detail, it is to be understood that'the applicant is not to b limited to the precise construction shown as various changes may be made in the construction, proportion and arrangement of parts without departing from the spirit of the invention or the scope of the appended claims.

I claim:

1. Absorption refrigerating apparatus comprising an inert gas circuit including an evaporator and an absorber, a solution circuit including a boiler and said absorber, power driven means for circulating the inert gas through said inert gas circuit, a fuel burner arranged to heat said boiler, fuel supply means for said burner, electrical igniting means for said burner, refrigeration demand responsive means for controlling the energization of said power driven inert gas circulator and of said electrical igniting means, and means controlling said fuel supply means arranged to be operated to fuel supplying condition only when i said igniting means has been energized by said refrigeration demand responsive means.

2. Absorption refrigerating apparatus comprising an inertgas circuit including an evaporator and an absorber, a solution circuit including a boiler and said absorber, power driven means. for circulating the inert gas through said inert gas circuit, a fuel burner arranged to heat said boiler, fuel supply means for said burner, electrical igniting means for said burner, refrigeration demand responsive means for controlling the energization of said power driven inert gas circulator and of said igniting means, means controlling said fuel supply means arranged to be operated to fuel supplying condition only when said igniting means has been energized by said refrigeration demand responsive means, and means for de-energizing said igniting means after initial energization thereof without deenergizing said power driven circulator.

3. Absorption refrigerating apparatus comprising an inert gas circuit including an evaporator and an absorber, a solutioncircuit including a boiler and said absorber, power driven means for circulating the inert gas through said inert gas circuit, a fuel burner arranged to heat said boiler, fuel supply means for said burner, igniting means for said burner, refrigeration demand responsive means for controlling the energization of said power driven inert gas circulator and of said igniting means, means controlling said fuel supply means arranged to be operated to fuel supplying condition only when said igniting means has been energized by said refrigeration demand responsive means, and means responsive to ignition of said burner for maintaining said fuel supply control means in fuel supplying condition.

'4. Absorption-refrigerating apparatus comprising an inert gas circuit including an evaporator and an absorber, a solution circuit including a boiler and said absorber, powerLdriven means for circulating the inert gas through said inert gas circuit, a fuel burner arranged to heat said boiler, fuel supply means for said burner, igniting means for said burner, refrigeration demand responsive means forcontrolling' the energization of said power driven inert gas circulator and of said igniting means, means controlling said fuel supply means arranged to be operated to fuel supplying condition only when said igniting means has been energized by said refrigeration demand responsive means, means for de-energizing said igniting means after initial energization thereof without de-energizing said power driven circulator, and means responsive to the presence of a flame on said burner for moving said igniting means away from such flame.

5. Refrigerating apparatus comprising a cabinet including an insulated storage compartment and a mechanism compartment, an absorption refrigerating apparatus including a generator in said mechanism compartment and a cooling unit in said storage compartment, a fuel burner ar-' electrical igniting device for said fuel burner, and

. refrigeration production control means for controlling the' supply of fuel to said burner and the operation of said electrical igniting device.

6-. Absorption refrigerating apparatus comprising an inert gas'circuit including an evaporator and an absorber, a solution circuit including a boiler and said absorber, means for liquefying refrigerant vapor produced in said boiler and for supplying the liquid to said evaporator, a fuel I burner arranged to heat said boiler, fuel supply '1. Absorption refrigerating apparatus comprising an inert gas circuit including an evaporator and an'absorbena solution circuit including a boiler and said absorber, means for liquefying refrigerant vapor produced in said boiler and for supplying the, liquid to said evaporator, a fuel burner arranged to heat said boiler, fuel supply means for said burner, a safety .cut-ofl. valve in said fuel supply means, a thermostat positioned to be heated by said burner for maintaining said safety cut-ofl valve in closed position when not heated, an electrical heater for heating said thermostat, an electrical igniter for said burner,

and refrigeration control mechanismfor governing the energization of said electrical heater and said igniter.

8. Absorption refrigerating apparatus comprising an inert gas circuit including an evaporator and an absorber, a solution circuit including a boiler and said absorber, means for liquefying refrigerant vapor produced in said boiler and for supplying the liquid to said evaporator, a fuel burner arranged to heat said boiler, fuel supply means for said burner, a safety cut-01f valve in said fuel supply means, a thermostat positioned to be heated by said burner for maintaining said safety cut-off valve in closed position when not heated, an electrical heater for heating said thermostat, an'electrical igniter for said burner, refrigeration control mechanism for governing the energization of said electrical heater and said igniter, means for deenergizing said electrical heater and said igniter after a period of energization thereof sufficient to open said valve and to ignite fuel issuing from said burner.

9. Absorption refrigerating apparatus comprising an inert gas circuit including an evaporator and an absorber, a solution circuit including a boiler and said absorber, means for liquefying refrigerant vapor produced in said boiler and for supplying the liquid to said evaporator, a fuel burner arranged to heat said boiler, fuel supply means for said burner, a solenoid valve controlling the flow of fuel to said burner, an electrical igniter for said burner, refrigeration demand responsive means for governing the operation of said valve and of said igniter, and flame respon sive means for de-energizlng said igniter after ignition of said burner.

10. Absorption refrigerating apparatus com: prising a boiler, a power operated fluid circu lator, a fuel burner arranged to heat said boiler, fuel supply means for said burner, electrica1 igniting means for said burner, refrigeration demand responsive means for controlling the energization' of said power driven circulator and of said igniting means, and means controlling said fuel supply means arranged to be operated to fuel supplying condition only when said igniting means has been energized by said refrigeration demand responsive means.

11. Absorption refrigerating apparatus comprising a boiler, a power driven fluidcirculator, a fuel burner for heating said boiler, fuel supply means for said burner, a valve in control of said fuel supply means, a thermostatic refrigeration demand responsive means in control of said valve and said circulator, an electrical igniter for said burner under the control of said thermostatic .means, and means for discontinuing operation of said electrical igniter withoutaifecting said burner after said igniter and said fuel supply valve bumer, condition responsive means for governing the energization of saidfluld circulator and of said ignition means, means adapted to be energized by said condition responsive means for supplying fuel to sald burner coincident with the energization of said ignition means, and means energized by the heat of said burner for maintaining the supply of fuel to said burner after ignition thereof 13. In combination, a power operated fluid circulator, a fuel burner, an ignition means for said burner, condition responsive means for governing the energization of said fluid circulator and of said ignition means, means adapted to be energized by said condition responsive means for sup-, plying fuel to said burner coincident with the energization'of said ignition means, and means energizedby the heat of said burner for maintaining the supplyof fuel to said burner after ignition thereof, and for de-energizing said ignition means without de-energizing said fuel burnor and said fluid circulator.

14. In a refrigerating apparatus of the absorption type; a generator, an evaporator, a condenser, an absorber and a power driven fluid circulator connected in circuit; a gas burner for heating said generator, a valve for controlling the supply of gas to said burner, thermostatic means arranged to be heated by said burner and to operate said valve to prevent the supply of gas to said burner when cold, an electrical heating device arranged to heat said thermostatic means to cause said thermostatic means to operate said valve to supply gas to said blirner, refrigeration demand responsive means arranged to energize said electrical heating device, and said power driven fluid circulator, and means operated by said thermostatic means for de-energizing said electrical heating device when said Valve has been operated to open position.

15. In a refrigerating apparatus of the absorption type; a generator, an evaporator, a condenser, an absorber and a power driven fluid circulator connected in circuit; a gas burner for heating said generator, a valve for controlling the supply of gas to said burner, thermostatic means arranged to be heated by said burner and to operate said valve to prevent the supply of gas to said burner when cold, an electrical heating device arranged to heat said thermostatic means to cause said thermostatic means to operate said valve to supply gas to said burner, an electrical igniter for said burner, refrigeration demand responsive means arranged to energize said elecculator, and means actuated by said thermoing a boiler and said absorber, power driven means for circulating the inert gas through said inert gas circuit, a fuel burner arranged to heat said boiler, fuel supply means for said burner,

igniting means for said burner, a thermostatic valve arranged to be heated by said burner in control of the fuel supply to said burner, electrical heating means for said thermostatic valve, refrigeration demand responsive means arranged to govern the energization of said electrical heating means, said igniting means and said power driven circulating means, and means operable to de -energize said electrical heating means and said igniting means when said burner is ignited.

18. Absorption refrigerating apparatus comprising an inert gas circuit including an evaporator and an absorber, a solution circuit including a boiler and said absorber, power driven means for circulating the inert gas through said inert gas circuit, a fuel burner arranged to heat said boiler, fuel supply means for said burner,

igniting means for said burner, a valve for conheating means, said igniting means and said power driven circulator in response toa demand for refrigeration.

19. Absorption refrigerating apparatus comprising aninert gas circuit including an evapotrical heating device and said electrical igniter igniter for said burner, thermostatic means arranged to position said igniter adjacent said burner in igniting relationship therewith and to move said igniter away from said burner after ignition thereof, refrigeration demand responsive means arranged to open said valve and to energize said igniter and said power driven fluid cirrator and an absorber, a solution circuit including a boiler and said absorber, power driven means for circulating the inert gas through said inert gas circuit, a fuel burner arranged to heat said boiler, fuel supply means for said burner, igniting means for said burner, a valve for controlling the supply of fuel to said burner, a thermostat arranged to open said valve when heated, electrical heating means arranged to heat said thermostat, a de-energizing switch in control of said electrical heating. means and said igniting means, said deenergizing switch being arranged to be operated to open circuit position by said thermostat when heated, and refrigeration con- CURTIS C. COONS. 

